Using fiemap without FIEMAP_FLAG_SYNC is a known corrupter.
Add the FIEMAP_FLAG_SYNC flag to the FS_IOC_FIEMAP ioctl. This has
the downside of significantly reducing performance.
Reported-By: Michael Steffens <michael_steffens@posteo.de>
Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Max Reitz <mreitz@redhat.com>
Cc: Pádraig Brady <pbrady@redhat.com>
Cc: Eric Blake <eblake@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
When the Qcow2DiscardRegion is adjacent to another one referenced by "d",
free this Qcow2DiscardRegion metadata referenced by "p" after
it was removed from s->discards queue.
Signed-off-by: Zhang Haoyu <zhanghy@sangfor.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Just like lazy-refcounts, this field will be present iff the qcow2
compat level is 1.1 (or probably any future revision).
As expected, this breaks some tests due to the new field present in
qemu-img info output; so fix their output accordingly.
Suggested-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1412105489-7681-3-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
$ ./qemu-img create -f qcow2 overlay \
-b 'json: { "file.driver":"ssh",
"file.host":"localhost",
"file.host_key_check":"no" }'
qemu-img: qobject/qdict.c:193: qdict_get_obj: Assertion `obj != ((void *)0)' failed.
Aborted
A similar crash also happens if the file.host field is omitted.
https://bugzilla.redhat.com/show_bug.cgi?id=1147343
Bug found and reported by Jun Li.
Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
Reviewed-by: Gonglei <arei.gonglei@huawei.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
yet 100% thread-safe, though, which makes it really, really
experimental. It also brings asynchronous cancellation to
the SCSI subsystem and implements it in virtio-scsi. This
is a pretty important feature. Almost all the work here
was done by Fam Zheng.
I also included the virtio refcount fixes from Gonglei,
because they had a small conflict with virtio-scsi dataplane.
This pull request is using the new subkey 4E6B09D7.
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Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging
This update brings dataplane to virtio-scsi (NOT
yet 100% thread-safe, though, which makes it really, really
experimental. It also brings asynchronous cancellation to
the SCSI subsystem and implements it in virtio-scsi. This
is a pretty important feature. Almost all the work here
was done by Fam Zheng.
I also included the virtio refcount fixes from Gonglei,
because they had a small conflict with virtio-scsi dataplane.
This pull request is using the new subkey 4E6B09D7.
# gpg: Signature made Tue 30 Sep 2014 12:31:02 BST using RSA key ID 4E6B09D7
# gpg: Good signature from "Paolo Bonzini <pbonzini@redhat.com>"
# gpg: aka "Paolo Bonzini <bonzini@gnu.org>"
* remotes/bonzini/tags/for-upstream: (39 commits)
block/iscsi: handle failure on malloc of the allocationmap
util: introduce bitmap_try_new
virtio-scsi: Handle TMF request cancellation asynchronously
scsi: Introduce scsi_req_cancel_async
scsi: Introduce scsi_req_cancel_complete
scsi: Drop SCSIReqOps.cancel_io
scsi: Unify request unref in scsi_req_cancel
scsi-generic: Handle canceled request in scsi_command_complete
scsi: Drop scsi_req_abort
virtio-scsi: Process ".iothread" property
virtio-scsi: Call bdrv_io_plug/bdrv_io_unplug in cmd request handling
virtio-scsi: Batched prepare for cmd reqs
virtio-scsi: Two stages processing of cmd request
virtio-scsi: Add migration state notifier for dataplane code
virtio-scsi: Hook up with dataplane
virtio-scsi-dataplane: Code to run virtio-scsi on iothread
virtio-scsi: Add VirtIOSCSIVring in VirtIOSCSIReq
virtio-scsi: Add 'iothread' property to virtio-scsi
virtio: add a wrapper for virtio-backend initialization
virtio-9p: fix virtio-9p child refcount in transports
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Check for the presence of posix_fallocate() in configure and only
compile in support for PREALLOC_MODE_FALLOC when it's there.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
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Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging
Block patches
# gpg: Signature made Fri 26 Sep 2014 19:57:52 BST using RSA key ID C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"
* remotes/kevin/tags/for-upstream:
qemu-iotests: Fail test if explicit test case number is unknown
block: Validate node-name
vpc: fix beX_to_cpu() and cpu_to_beX() confusion
docs: add blkdebug block driver documentation
block: Catch simultaneous usage of options and their aliases
block: Specify -drive legacy option aliases in array
block: Improve message for device name clashing with node name
qemu-nbd: Destroy the BlockDriverState properly
block: Keep DriveInfo alive until BlockDriverState dies
blockdev: Disentangle BlockDriverState and DriveInfo creation
blkdebug: show an error for invalid event names
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
iscsi_aio_write16_cb, iscsi_aio_writev, iscsi_aio_read16_cb, and
iscsi_aio_readv have not not been in use since commit
063c3378a9 ("block/iscsi: introduce
bdrv_co_{readv, writev, flush_to_disk}").
These were the only trace events in block/iscsi.c so drop the the
trace.h include.
Cc: Peter Lieven <pl@kamp.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-id: 1411394595-15300-4-git-send-email-stefanha@redhat.com
The beX_to_cpu() and cpu_to_beX() functions perform the same operation -
they do a byteswap if the host CPU endianness is little-endian or a
nothing otherwise.
The point of two names for the same operation is that it documents which
direction the data is being converted. This makes it clear whether the
data is suitable for CPU processing or in its external representation.
This patch fixes incorrect beX_to_cpu()/cpu_to_beX() usage.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
It is easy to typo a blkdebug configuration and waste a lot of time
figuring out why no rules are matching.
Push the Error** down into add_rule() so we can report an error when the
event name is invalid.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Gonglei <arei.gonglei@huawei.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
In vhdx_create_metadata(), we allocate 40 bytes to entry_buffer for
the various metadata table entries. However, we write out 64kB from
that buffer into the new file. Only write out the correct 40 bytes.
Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This patch removes support for the cow file format.
Normally we do not break backwards compatibility but in this case there
is no impact and it is the most logical option. Extraordinary claims
require extraordinary evidence so I will show why removing the cow block
driver is the right thing to do.
The cow file format is the disk image format for Usermode Linux, a way
of running a Linux system in userspace. The performance of UML was
never great and it was hacky, but it enjoyed some popularity before
hardware virtualization support became mainstream.
QEMU's block/cow.c is supposed to read this image file format.
Unfortunately the file format was underspecified:
1. Earlier Linux versions used the MAXPATHLEN constant for the backing
filename field. The value of MAXPATHLEN can change, so Linux
switched to a 4096 literal but QEMU has a 1024 literal.
2. Padding was not used on the header struct (both in the Linux kernel
and in QEMU) so the struct layout varied across architectures. In
particular, i386 and x86_64 were different due to int64_t alignment
differences. Linux now uses __attribute__((packed)), QEMU does not.
Therefore:
1. QEMU cow images do not conform to the Linux cow image file format.
2. cow images cannot be shared between different host architectures.
This means QEMU cow images are useless and QEMU has not had bug reports
from users actually hitting these issues.
Let's get rid of this thing, it serves no purpose and no one will be
affected.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-id: 1410877464-20481-1-git-send-email-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Being able to set the overlap-check option to a string and then refine
it via the overlap-check.* options is a nice idea for the command line
but does not work so well for non-flattened dicts. In that case, one can
only specify either but not both, so add a field to overlap-check.*
which does the same as directly specifying overlap-check but can be used
in conjunction with the other fields in non-flattened dicts.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1408557576-14574-4-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Currently, the QemuOpts object opts is leaked if anything fails from its
creation up to and including the image repair block. Fix this by freeing
that object in the fail path.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Message-id: 1408557576-14574-2-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Offsets taken from the L1, L2 and refcount tables are generally assumed
to be correctly aligned. However, this cannot be guaranteed if the image
has been written to by something different than qemu, thus check all
offsets taken from these tables for correct cluster alignment.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1409926039-29044-5-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Use the new function in case of a failed overlap check.
This changes output in case of corruption, so adapt iotest 060's
reference output accordingly.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Message-id: 1409926039-29044-4-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Add a helper function for easily marking an image corrupt (on fatal
corruptions) while outputting an informative message to stderr and via
QAPI.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Message-id: 1409926039-29044-3-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Not every BLOCK_IMAGE_CORRUPTED event must be fatal; for example, when
reading from an image, they should generally not be. Nonetheless, even
an image only read from may of course be corrupted and this can be
detected during normal operation. In this case, a non-fatal event should
be emitted, but the image should not be marked corrupt (in accordance to
"fatal" set to false).
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1409926039-29044-2-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This is an analogue to Linux null_blk. It can be used for testing or
benchmarking block device emulation and general block layer
functionalities such as coroutines and throttling, where disk IO is not
necessary or wanted.
Use null-aio:// for AIO version, and null-co:// for coroutine version.
[Resolved conflict with Fam's async bdrv_aio_cancel() series:
1. Drop .bdrv_aio_cancel() since it is now done by block.c
2. Rename qemu_aio_release() to qemu_aio_unref()
--Stefan]
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1410415798-20673-2-git-send-email-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Also drop the now unused SheepdogAIOCB.finished field. Note that this
aio is internal to sheepdog driver and has NULL cb and opaque, and
should be unused at all.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Before, we cancel all the child requests with bdrv_aio_cancel, then free
the acb..
Now we just kick off asynchronous cancellation of child requests and
return, we know quorum_aio_cb will be called later, so in the end
quorum_aio_finalize will take care of calling the caller's cb.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
For a fifo read pattern, we only have one running aio (possible other cases that
has less number than num_children in the future), so we need to check if
.acb is NULL against bdrv_aio_cancel() to avoid segfault.
Cc: Eric Blake <eblake@redhat.com>
Cc: Benoit Canet <benoit@irqsave.net>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Liu Yuan <namei.unix@gmail.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The cancelled flag is no longer useful. Later the request will complete
as before, and cb will be called.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Just call io_cancel (2), if it fails, it means the request is not
canceled, so the event loop will eventually call
qemu_laio_process_completion.
In qemu_laio_process_completion, change to call the cb unconditionally.
It is required by bdrv_aio_cancel_async.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The parent_vhdx_guid variable is defined but never used, which provokes
complaints from newer versions of clang. Since the variable definition
is here acting as documentation of the image format, mark it with the
'unused' attribute to keep the compiler happy rather than simply
deleting it.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
When trying to create a fixed vhd image qemu-img will return the
following error:
qemu-img: test.vhdx: Could not create image: Cannot allocate memory
This happens because of a incorrect check in vhdx.c. Specifficaly,
in vhdx_create_bat(), after allocating memory for the BAT entry,
there is a check to determine if the allocation was unsuccsessful.
The error comes from the fact that it checks if s->bat isn't NULL,
which is true in case of succsessful allocation, and exits with
error ENOMEM.
Signed-off-by: Adelina Tuvenie <atuvenie@cloudbasesolutions.com>
Acked-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
preallocation=falloc allocates disk space by posix_fallocate(),
preallocation=full allocates disk space by writing zeros to disk.
Both modes imply preallocation=metadata.
Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This patch adds a new option preallocation for raw format, and implements
falloc and full preallocation.
Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This patch prepares for the subsequent patches.
Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
and avoid converting it back later.
Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Currently the file size requested by user is rounded down to nearest
sector, causing the actual file size could be a bit less than the size
user requested. Since some formats (like qcow2) record virtual disk
size in bytes, this can make the last few bytes cannot be accessed.
This patch fixes it by rounding up file size to nearest sector so that
the actual file size is no less than the requested file size.
Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This is the next step for decoupling block accounting functions from
BlockDriverState.
In a future commit the BlockAcctStats structure will be moved from
BlockDriverState to the device models structures.
Note that bdrv_get_stats was introduced so device models can retrieve the
BlockAcctStats structure of a BlockDriverState without being aware of it's
layout.
This function should go away when BlockAcctStats will be embedded in the device
models structures.
CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Keith Busch <keith.busch@intel.com>
CC: Anthony Liguori <aliguori@amazon.com>
CC: "Michael S. Tsirkin" <mst@redhat.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Eric Blake <eblake@redhat.com>
CC: Peter Maydell <peter.maydell@linaro.org>
CC: Michael Tokarev <mjt@tls.msk.ru>
CC: John Snow <jsnow@redhat.com>
CC: Markus Armbruster <armbru@redhat.com>
CC: Alexander Graf <agraf@suse.de>
CC: Max Reitz <mreitz@redhat.com>
Signed-off-by: Benoît Canet <benoit.canet@nodalink.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The middle term goal is to move the BlockAcctStats structure in the device models.
(Capturing I/O accounting statistics in the device models is good for billing)
This patch make a small step in this direction by removing a reference to BDRV.
CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Keith Busch <keith.busch@intel.com>
CC: Anthony Liguori <aliguori@amazon.com>
CC: "Michael S. Tsirkin" <mst@redhat.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: John Snow <jsnow@redhat.com>
CC: Richard Henderson <rth@twiddle.net>
CC: Markus Armbruster <armbru@redhat.com>
CC: Alexander Graf <agraf@suse.de>i
Signed-off-by: Benoît Canet <benoit.canet@nodalink.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The plan is to add new accounting metrics (latency, invalid requests, failed
requests, queue depth) and block.c is overpopulated so it will be better to work
in a separate module.
Moreover the long term plan is to have statistics in each of the BDS of the graph
for metrology purpose; this means that the device model statistics must move from
the topmost BDS to the device model.
So we need to decouple the statistic code from BlockDriverState.
This is another argument for the extraction of the code in a separate module.
CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Max Reitz <mreitz@redhat.com>
CC: Eric Blake <eblake@redhat.com>
CC: Benoit Canet <benoit@irqsave.net>
CC: Fam Zheng <famz@redhat.com>
CC: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Benoît Canet <benoit.canet@nodalink.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Extract the block accounting statistics into a structure so the block device
models can hold them in the future.
CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Max Reitz <mreitz@redhat.com>
CC: Eric Blake <eblake@redhat.com>
Signed-off-by: Benoît Canet <benoit.canet@nodalink.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
cpu_to_be32() is wrong since vhd_type is an enum constant
(just a regular CPU-endian integer).
Signed-off-by: Xiaodong Gong <gordongong0350@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
vmdk_open_sparse() does not take ownership of buf so the caller always
needs to free it.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Replace __sync builtins with ones provided by QEMU
for atomic operations.
Special thanks goes to Paolo Bonzini for his refactoring
suggestion in order to use the already existing atomic builtins
interface.
Signed-off-by: Chrysostomos Nanakos <cnanakos@grnet.gr>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
In commit 63f0f45f2e the following
mechanical change was made:
if (!state) {
- qemu_aio_wait();
+ aio_poll(state->s->aio_context, true);
}
The new code now checks if state is NULL and then dereferences it
('state->s') which is obviously incorrect.
This commit replaces state->s->aio_context with
bdrv_get_aio_context(bs), fixing this problem. The two other hunks
are concerned with getting the BlockDriverState pointer bs to where it
is needed.
The original bug causes a segfault when using libguestfs to access a
VMware vCenter Server and doing any kind of complex read-heavy
operations. With this commit the segfault goes away.
Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
In order to access VMware ESX efficiently, we need to send a session
cookie. This patch is very simple and just allows you to send that
session cookie. It punts on the question of how you get the session
cookie in the first place, but in practice you can just run a `curl'
command against the server and extract the cookie that way.
To use it, add file.cookie to the curl URL. For example:
$ qemu-img info 'json: {
"file.driver":"https",
"file.url":"https://vcenter/folder/Windows%202003/Windows%202003-flat.vmdk?dcPath=Datacenter&dsName=datastore1",
"file.sslverify":"off",
"file.cookie":"vmware_soap_session=\"52a01262-bf93-ccce-d379-8dabb3e55560\""}'
image: [...]
file format: raw
virtual size: 8.0G (8589934592 bytes)
disk size: unavailable
Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
If two Linux AIO request completions are fetched in the same
io_getevents() call, QEMU will deadlock if request A's callback waits
for request B to complete using an aio_poll() loop. This was reported
to happen with the mirror blockjob.
This patch moves completion processing into a BH and makes it resumable.
Nested event loops can resume completion processing so that request B
will complete and the deadlock will not occur.
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Ming Lei <ming.lei@canonical.com>
Cc: Marcin Gibuła <m.gibula@beyond.pl>
Reported-by: Marcin Gibuła <m.gibula@beyond.pl>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Tested-by: Marcin Gibuła <m.gibula@beyond.pl>
We should reinit local_err as NULL inside the while loop or g_free() will report
corrupption and abort the QEMU when sheepdog driver tries reconnecting.
This was broken in commit 356b4ca.
qemu-system-x86_64: failed to get the header, Resource temporarily unavailable
qemu-system-x86_64: Failed to connect to socket: Connection refused
qemu-system-x86_64: (null)
[xcb] Unknown sequence number while awaiting reply
[xcb] Most likely this is a multi-threaded client and XInitThreads has not been called
[xcb] Aborting, sorry about that.
qemu-system-x86_64: ../../src/xcb_io.c:298: poll_for_response: Assertion `!xcb_xlib_threads_sequence_lost' failed.
Aborted (core dumped)
Cc: qemu-devel@nongnu.org
Cc: Markus Armbruster <armbru@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Liu Yuan <namei.unix@gmail.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Uses the same select/WSAEventSelect scheme as main-loop.c.
WSAEventSelect() is edge-triggered, so it cannot be used
directly, but it is still used as a way to exit from a
blocking g_poll().
Before g_poll() is called, we poll sockets with a non-blocking
select() to achieve the level-triggered semantics we require:
if a socket is ready, the g_poll() is made non-blocking too.
Based on a patch from Or Goshen.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This patch adds single read pattern to quorum driver and quorum vote is default
pattern.
For now we do a quorum vote on all the reads, it is designed for unreliable
underlying storage such as non-redundant NFS to make sure data integrity at the
cost of the read performance.
For some use cases as following:
VM
--------------
| |
v v
A B
Both A and B has hardware raid storage to justify the data integrity on its own.
So it would help performance if we do a single read instead of on all the nodes.
Further, if we run VM on either of the storage node, we can make a local read
request for better performance.
This patch generalize the above 2 nodes case in the N nodes. That is,
vm -> write to all the N nodes, read just one of them. If single read fails, we
try to read next node in FIFO order specified by the startup command.
The 2 nodes case is very similar to DRBD[1] though lack of auto-sync
functionality in the single device/node failure for now. But compared with DRBD
we still have some advantages over it:
- Suppose we have 20 VMs running on one(assume A) of 2 nodes' DRBD backed
storage. And if A crashes, we need to restart all the VMs on node B. But for
practice case, we can't because B might not have enough resources to setup 20 VMs
at once. So if we run our 20 VMs with quorum driver, and scatter the replicated
images over the data center, we can very likely restart 20 VMs without any
resource problem.
After all, I think we can build a more powerful replicated image functionality
on quorum and block jobs(block mirror) to meet various High Availibility needs.
E.g, Enable single read pattern on 2 children,
-drive driver=quorum,children.0.file.filename=0.qcow2,\
children.1.file.filename=1.qcow2,read-pattern=fifo,vote-threshold=1
[1] http://en.wikipedia.org/wiki/Distributed_Replicated_Block_Device
[Dropped \n from an error_setg() error message
--Stefan]
Cc: Benoit Canet <benoit@irqsave.net>
Cc: Eric Blake <eblake@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Liu Yuan <namei.unix@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Recently, sheepdog revived its VDI locking functionality. This patch
updates sheepdog driver of QEMU for this feature. It changes an error
code for a case of failed locking. -EBUSY is a suitable one.
Reported-by: Valerio Pachera <sirio81@gmail.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Liu Yuan <namei.unix@gmail.com>
Cc: MORITA Kazutaka <morita.kazutaka@gmail.com>
Signed-off-by: Hitoshi Mitake <mitake.hitoshi@lab.ntt.co.jp>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The update is required for supporting iSCSI multipath. It doesn't
affect behavior of QEMU driver but adding a new field to vdi request
struct is required.
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Liu Yuan <namei.unix@gmail.com>
Cc: MORITA Kazutaka <morita.kazutaka@gmail.com>
Signed-off-by: Hitoshi Mitake <mitake.hitoshi@lab.ntt.co.jp>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The curl hardcoded timeout (5 seconds) sometimes is not long
enough depending on the remote server configuration and network
traffic. The user should be able to set how much long he is
willing to wait for the connection.
Adding a new option to set this timeout gives the user this
flexibility. The previous default timeout of 5 seconds will be
used if this option is not present.
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Daniel Henrique Barboza <danielhb@linux.vnet.ibm.com>
Reviewed-by: Benoit Canet <benoit.canet@nodalink.com>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The gcc 4.1.2 compiler warns that delay_ns may be uninitialized in
mirror_iteration().
There are two break statements in the do ... while loop that skip over
the delay_ns assignment. These are probably the cause of the warning.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Instead of bdrv_getlength().
Commit 57322b7 did this all over block, but one more bdrv_getlength()
has crept in since.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Otherwise error_callback_bh will access the already released acb.
Cc: qemu-stable@nongnu.org
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The following O_DIRECT read from a <512 byte file fails:
$ truncate -s 320 test.img
$ qemu-io -n -c 'read -P 0 0 512' test.img
qemu-io: can't open device test.img: Could not read image for determining its format: Invalid argument
Note that qemu-io completes successfully without the -n (O_DIRECT)
option.
This patch fixes qemu-iotests ./check -nocache -vmdk 059.
Cc: qemu-stable@nongnu.org
Suggested-by: Kevin Wolf <kwolf@redhat.com>
Reported-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
bs->total_sectors is not yet updated at this point. resulting
in memory corruption if the volume has grown and data is written
to the newly availble areas.
CC: qemu-stable@nongnu.org
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Just log to stderr unconditionally, like other similar code does.
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Because blkdebug cannot simply create a configuration file, simply
refuse to reconstruct a plain filename and only generate an options
QDict from the rules instead.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Add options for specifying the size of the metadata caches. This can
either be done directly for each cache (if only one is given, the other
will be derived according to a default ratio) or combined for both.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
With a variable cache size, the number given to qcow2_cache_create() may
be huge. Therefore, use g_try_new0().
While at it, use g_new0() instead of g_malloc0() for allocating the
Qcow2Cache object.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Specifying the metadata cache sizes in clusters results in less clusters
(and much less bytes) covered for small cluster sizes and vice versa.
Using a constant byte size reduces this difference, and makes it
possible to manually specify the cache size in an easily comprehensible
unit.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
They clutter the code. Unfortunately, I can't figure out how to make
Coccinelle drop all of them, so I have to settle for common special
cases:
@@
type T;
T *pt;
void *pv;
@@
- pt = (T *)pv;
+ pt = pv;
@@
type T;
@@
- (T *)
(\(g_malloc\|g_malloc0\|g_realloc\|g_new\|g_new0\|g_renew\|
g_try_malloc\|g_try_malloc0\|g_try_realloc\|
g_try_new\|g_try_new0\|g_try_renew\)(...))
Topped off with minor manual style cleanups.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
g_new(T, n) is safer than g_malloc(sizeof(*v) * n) for two reasons.
One, it catches multiplication overflowing size_t. Two, it returns
T * rather than void *, which lets the compiler catch more type
errors.
Perhaps a conversion to g_malloc_n() would be neater in places, but
that's merely four years old, and we can't use such newfangled stuff.
This commit only touches allocations with size arguments of the form
sizeof(T), plus two that use 4 instead of sizeof(uint32_t). We can
make the others safe by converting to g_malloc_n() when it becomes
available to us in a couple of years.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
g_new(T, n) is neater than g_malloc(sizeof(T) * n). It's also safer,
for two reasons. One, it catches multiplication overflowing size_t.
Two, it returns T * rather than void *, which lets the compiler catch
more type errors.
Patch created with Coccinelle, with two manual changes on top:
* Add const to bdrv_iterate_format() to keep the types straight
* Convert the allocation in bdrv_drop_intermediate(), which Coccinelle
inexplicably misses
Coccinelle semantic patch:
@@
type T;
@@
-g_malloc(sizeof(T))
+g_new(T, 1)
@@
type T;
@@
-g_try_malloc(sizeof(T))
+g_try_new(T, 1)
@@
type T;
@@
-g_malloc0(sizeof(T))
+g_new0(T, 1)
@@
type T;
@@
-g_try_malloc0(sizeof(T))
+g_try_new0(T, 1)
@@
type T;
expression n;
@@
-g_malloc(sizeof(T) * (n))
+g_new(T, n)
@@
type T;
expression n;
@@
-g_try_malloc(sizeof(T) * (n))
+g_try_new(T, n)
@@
type T;
expression n;
@@
-g_malloc0(sizeof(T) * (n))
+g_new0(T, n)
@@
type T;
expression n;
@@
-g_try_malloc0(sizeof(T) * (n))
+g_try_new0(T, n)
@@
type T;
expression p, n;
@@
-g_realloc(p, sizeof(T) * (n))
+g_renew(T, p, n)
@@
type T;
expression p, n;
@@
-g_try_realloc(p, sizeof(T) * (n))
+g_try_renew(T, p, n)
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Commit de82815db1 ("qcow2: Handle failure
for potentially large allocations") introduced a double-free of
new_blocks in the alloc_refcount_block() error path.
The qemu-iotests qcow2 026 test case was failing because qemu-io
segfaulted.
Make sure new_blocks is NULL after we free it the first time.
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Parallels has released in the recent updates of Parallels Server 5/6
new addition to his image format. Images with signature WithouFreSpacExt
have offsets in the catalog coded not as offsets in sectors (multiple
of 512 bytes) but offsets coded in blocks (i.e. header->tracks * 512)
In this case all 64 bits of header->nb_sectors are used for image size.
This patch implements support of this for qemu-img and also adds specific
check for an incorrect image. Images with block size greater than
INT_MAX/513 are not supported. The biggest available Parallels image
cluster size in the field is 1 Mb. Thus this limit will not hurt
anyone.
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Jeff Cody <jcody@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
and rework error path a bit. There is no difference at the moment, but
the code will be definitely shorter when additional processing will
be required for WithouFreSpacExt
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Jeff Cody <jcody@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Jeff Cody <jcody@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Parallels image format has several additional fields inside:
- nb_sectors is actually 64 bit wide. Upper 32bits are not used for
images with signature "WithoutFreeSpace" and must be explicitly
zeroed according to Parallels. They will be used for images with
signature "WithouFreSpacExt"
- inuse is magic which means that the image is currently opened for
read/write or was not closed correctly, the magic is 0x746f6e59
- data_off is the location of the first data block. It can be zero
and in this case data starts just beyond the header aligned to
512 bytes. Though this field does not matter for read-only driver
This patch adds these values to struct parallels_header and adds
proper handling of nb_sectors for currently supported WithoutFreeSpace
images.
WithouFreSpacExt will be covered in next patches.
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Jeff Cody <jcody@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
qcow2_alloc_cluster_offset() uses host_offset == 0 as "no preferred
offset" for the (data) cluster range to be allocated. However, this
offset is actually valid and may be allocated on images with a corrupted
refcount table or first refcount block.
In this case, the corruption prevention should normally catch that
write anyway (because it would overwrite the image header). But since 0
is a special value here, the function assumes that nothing has been
allocated at all which it asserts against.
Because this condition is not qemu's fault but rather that of a broken
image, it shouldn't throw an assertion but rather mark the image corrupt
and show an appropriate message, which this patch does by calling the
corruption check earlier than it would be called normally (before the
assertion).
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
If bdrv_pread() returns an error, it is very unlikely that it was
ENOMEM. In this case, the return value should be passed along; as
bdrv_pread() will always either return the number of bytes read or a
negative value (the error code), the condition for checking whether
bdrv_pread() failed can be simplified (and clarified) as well.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Some code in the block layer makes potentially huge allocations. Failure
is not completely unexpected there, so avoid aborting qemu and handle
out-of-memory situations gracefully.
This patch addresses the allocations in the mirror block job.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Some code in the block layer makes potentially huge allocations. Failure
is not completely unexpected there, so avoid aborting qemu and handle
out-of-memory situations gracefully.
This patch addresses the allocations in the vpc block driver.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Some code in the block layer makes potentially huge allocations. Failure
is not completely unexpected there, so avoid aborting qemu and handle
out-of-memory situations gracefully.
This patch addresses the allocations in the vmdk block driver.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Some code in the block layer makes potentially huge allocations. Failure
is not completely unexpected there, so avoid aborting qemu and handle
out-of-memory situations gracefully.
This patch addresses the allocations in the vhdx block driver.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Some code in the block layer makes potentially huge allocations. Failure
is not completely unexpected there, so avoid aborting qemu and handle
out-of-memory situations gracefully.
This patch addresses the allocations in the vdi block driver.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Some code in the block layer makes potentially huge allocations. Failure
is not completely unexpected there, so avoid aborting qemu and handle
out-of-memory situations gracefully.
This patch addresses the allocations in the rbd block driver.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Some code in the block layer makes potentially huge allocations. Failure
is not completely unexpected there, so avoid aborting qemu and handle
out-of-memory situations gracefully.
This patch addresses the allocations in the raw-win32 block driver.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Some code in the block layer makes potentially huge allocations. Failure
is not completely unexpected there, so avoid aborting qemu and handle
out-of-memory situations gracefully.
This patch addresses the allocations in the raw-posix block driver.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Some code in the block layer makes potentially huge allocations. Failure
is not completely unexpected there, so avoid aborting qemu and handle
out-of-memory situations gracefully.
This patch addresses the allocations in the qed block driver.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Some code in the block layer makes potentially huge allocations. Failure
is not completely unexpected there, so avoid aborting qemu and handle
out-of-memory situations gracefully.
This patch addresses the allocations in the qcow2 block driver.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Some code in the block layer makes potentially huge allocations. Failure
is not completely unexpected there, so avoid aborting qemu and handle
out-of-memory situations gracefully.
This patch addresses the allocations in the qcow1 block driver.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
